Process for resolving water-in-oil type emulsions



PROCESS FOR RESOLVING WATER-IN-OIL TYPE EMULSIONS Anthony J. Martinelli, Easton, Pa., assignor to General 2,826,554 Patented Mar. 11, 1958 available directly for use in the process and processes of this invention. The polymers which are operative in the instant invention have molecular weights ranging from about 300 up to several million or more. Viscosity measurements arecommonly used as an indication of the average molecular weight of polymeric compositions. The

Aniline & Film Corporation, New York, N.,Y., a corporation of Delaware No Drawing. Application June 23, 1 955 7 Serial N0. 517,640

'14 Clairns. (Cl. zsa-ssi This invention relates to processes or procedures for resolving emulsions of the water-in-oil type.

There are various liquid systems existing'in industry which are in the form of water-in-oil type emulsions, Which emulsions must be separated into their component parts of water and oil. Prime examples of such liquid systems are the petroleum emulsions commonly referred to as cut oil, roily oil, emulsified oil," etc., which are obtained from producing wells, pipelines from the bottomsof oil storage tanks, and the like, and Which comprise fine droplets of-naturally occurring waters or brines, dispersed in a more or less permanent state throughout the oil; the latter constituting thecontinuous phase of the emulsion. Water-:in-oil type emulsions are also formed under controlled conditions in processes for removing impurities, particularlydnorganic salts, from pipeline oil.

Other water-in-oil type emulsions encounteredin nature or industry include gas-tar emulsions, tar-sand-oil emulsions, emulsions encountered in the manufacture of antibiotic agents, emulsions encountered in the sweetening of caustic washing of hydrocarbons, and the like. i

It is an object of this invention to provide novel process and processes for resolving, breaking, or separating water- 'in-oil emulsions into their oily and aqueous component parts.

It is a further object of this invention to provide novel process and processes for resolving water-in-oil emulsions employing polymers of alkyl vinyl ether.

It is a still further object of this invention to provide novel process and processes for the resolving of waterin-oil emulsions by the addition thereto of polymers of methyl and ethyl ethers.

Other objects and advantages will appear as the description proceeds.

' The above recited objects are achieved by the present invention which comprises treating or subjecting waterin-oil type emulsions of the type described above to the action of polymers of alkyl vinyl ethers and, in particular, polymers of methyl and ethyl vinyl ethers, which are characterized by the formula:

it 0t wherein R is an alkyl group, preferably methyl or ethyl, and n has the value of at least 5. These polymeric alkyl K.value Fikentscher of any particular mixture of polymers is calculated from viscosity data and is useful as an indication of the average molecular weight of such mixture; The determination of the K value is fully described in Modern Plastics, vol. 23, No. 3, pp. 157-61, 212, 214, 216 and 218 (1945), and is defined as lOOO'times k in the empirical relative viscosity equation:

vinyl ethers are well known substances and are readily vinyl ethers having a K value of about 10 to 200, and

preferably from about 15 to 100.

K values and specific viscosities (,1. sp.) are interconvertible and are related through relative viscosity rel.). Thus, when viscosity measurements are taken on solutions which have a concentration of 1.00 g. polymer per deciliter of solution at 25 C. (C=l), the relations areas follows (l) ,u. rel.= .t sp.+l (2) Relative viscosity=specific viscosity-H (3) Relative viscosity=l0 [0'.001K+ 0.000075K3/(1+0.0015K)1 (4) ,u sp.=1+10 [0.001K+ Relative viscosity, specific viscosity, and K are dimensionless, whereas inherent viscosity (log ,u. rel.+C) and intrinsic viscosity (the limit of inherent viscosity as C approaches 0) have the dimensions of dilution, that is, the reciprocal of concentration. Intrinsic viscosity and K are intended to be independent of concentration.

The present invention may be put into practice for demulsification by introducing a relatively small proportion of a substance of the type described above, namely, polymers of alkyl vinyl ethers, into a relatively large proportion of the water-in-oil emulsion, admixing said substance and said emulsion with agitation in any of the various types of apparatus now generally used to resolve or break petroleum emulsions, or the like, with a chemical reagent. It may be desirable and indeedpreferable to apply'heat to the admixture, after which said mixture is allowed to stand quiescent until the undesirable Water content of the emulsion separates and settles from the oily mass. Slight agitation in the Water layer at this point is usually helpful in breaking a webbing that sometimes forms during Such demulsification process. The demulsifying agent or substance may be added directly to the emulsion or it may be first dissolved in and/ or diluted with any suitable liquid medium to produce a concentrate, or the like,

thereof. As suitable solvents and diluents, there may be included water, petroleum hydrocarbons, benzene, toluene, xylene, aliphatic alcohols, such as methyl alcohol, ethyl alcohol, denatured alcohol, propyl alcohol, isopropyl alcohol, butyl alcohol, the amyl alcohols, the octyl alcohols, mixtures thereof, and the like.

The demulsifying agent or substance may be employed as the sole demulsifier or it may be used in admixture with other suitable well known types of demulsifying agents. In view of the minute amounts of demulsifying agent employed, its solubility in the oil or water of the emulsion to be treated is of little significance. Thus, concentrations of the demulsifying agents of the order of from about 10 to about 500 parts by weight of demulsifier per million (p. p. m.) parts by volume of the emulsion are usually suflicient and adequate, although concentrations outside this range may, in some cases, be effective and economically feasible.

EXAMPLE 3 The same materials and procedure outlined above in Example 1 is repeated except that a 1% water solution of the polyvinyl methyl ether is employed. The effectiveness of this composition is demonstrated in Table 2.

EXAMPLE 4 The procedure of Example lfis repeated except that 0.15 ml. of the same demulsifying composition is employed per 100 mls. crude oil emulsion.

Table I DEMULSIFIOATION F CRUDE OIL EMULSION Oonpen- Shaking Heated 140 F., Shaking min, standing Demnlslfier tration, 30 min. Standing min. 10 min. i '16 min. swirled p. p. in. (color) Ex. 1: Polyvinyl Oil 4.2-dark green Oil 3.9Dark green..- Oil 3.9Dark green Oil-Dark green. methyl ether. 100 Dark green" {Water 2.8-Sllghtly webby.. Water 3.1-clear Water 3.1-Sltghtly webby.. Water-Clear.

Table 2 I DEMULSIFIOATION OF CRUDE OIL EMULSION S Goncen- Shaking Heated 140 F., Shaking 10 mln., standing Demulsifler tration, min. Standing 15 min. 10 min. 15 min. Swirled p. p. m. (color) Oil 4.0De.rk green Oil 3.9-Dark green.-. Oil 3.9Dark green OilDark green. Polyvmyl 100 Dark green-. Water 3.0-Slightly webby.. Water 3.1Clear Water 3.1-Very slightly Water-Clear.

methyl ether. webby. Ex P01 Vin 1 Oil 3.9-Dark green Oil 4.0-Dark Green-. Oil 3.9Dark green Oil-Dark green. i 100 --do Water 3.1-Very slightly Water 3.0Mostly Water 3.1Very slightly Water0lear.

y webby. clear. webby.

Ex. 4: Polyvinyl 15 Cocoa Oil 4.7-Cocoa Oil 4.4Dark green-.- Oil 4.0-Dark green OilDark green. methyl ether. Water 2.3-Very webby. Water 2.6Webby..... Water 3.0Web y-.. Water Clear. Ex P01 Vin 1 Oil 5.2-Light cocoa Oil 4.6-Cocoa Oil 4.0-Dark green-; Oil-Dark green. y y 15 Light cocoa. Water 1.8-Siightly webby. Water 2.4-Sl.ightly Water 3.0-Slightly webby.. Water-Clear.

methyl ether. webby.

Oil 4.0-Dark green Oil 4.0-Dark green... Oil 4.0-Dark green Oil-Dark green. fi'hpolyvmyl 15 Dark green.. Water 3.0-Very webby.. Water 3.0Mostly Water 3.0--Very slightly Water-Clear.

met 71 ether clear. webby.

The following examples will serve to illustrate the EXAMPLE 5 present invention without being limitative thereof.

EXAMPLE 1 One ml. of 1% solution of polyvinyl methyl ether in a solvent combination of 65 parts xylene and parts isopropyl alcohol is added to 100 mls. of crude oil emul sion contained in a 4 oz. bottle. The sample of polyvinyl methyl ether employed herein is characterized by having a relative viscosity of 1.77 and a specific viscosity of 0.77 which corresponds to a Fikentscher K value of 54.

The 4 oz. bottle containing the above described admixture is capped and mechanically shaken for 30 minutes. After removal from themechanical shaker, the bottle is allowed to stand quiescent for 15 minutes. The color of the sample and any water separation is noted. The bottle is then immersed in a water bath maintained at 140 F. (60 C.) for 10 minutes and any water separation is noted. The bottle is then returned to the mechanical shaker for another 10 minutes, removed, and permitted to stand quiescent for 15 minutes.

sultant color and Water drop are again noted. The bottle is then slightly agitated by swirling the contents thereof to break a webbing that forms on the water layer.

The results of this demulsifying agent are set forth in Table 1 wherein the heights of the water and oil layers are given in centimeters and the concentration of demulsifying agent is given in parts per million (p. p. m.).

ether dissolved in water.

The re- The procedure of Example 2 is repeated except that 0.15 ml. of the 1% isopropyl alcohol solution is employed.

EXAMPLE 6 The procedure of Example 3 is repeated except that 0.15 ml. of the 1% water solution of the polymer is employed. The results of Examples .4-6 are set forth in Table 2.

EXAMPLE 7 To mls. of a refinery emulsion, the composition of which is approximately 70 parts water, 20 parts oil, and 10 parts solids, contained in a 6 oz. bottle, there is added 3 mls. of a 1% solution of polyvinyl methyl The polyvinyl methyl ether employed herein is similar to the one in Examples 1-6. The results are set forth in Table 3.

EXAMPLE 8 To 100 mls. of a crude oil emulsion contained in a 4 oz. bottle, there is added 5 mls. of a 1% solution of polyvinyl ethyl ether dissolved in alcohol. The same procedure for determining the effectiveness of this composition is carried out as described in Example 1.

EXAMPLE 9 To 100 mls. of a crude oil emulsion contained in a 4 62. bottle, there is added 10 mls. of a 1% solution of a polyvinyl ethyl ether in alcohol. The same procedure as outlined in Example 1 is carried out to determine the elfectiveness of the demulsifying composition. The effectiveness of the compositions of Examples 8 and 9 are shown in Table 4.

9. A process as defined in claim 7 wherein the said polyvinyl methyl ether is employed in amounts of about 15 to 100 parts by weight per million parts by volume of said emulsion.

10. A process as defined in claim 8 wherein said polyvinyl methyl ether is employed in amounts up to about Table 3 DEMULSIFIOATION OF REFINERY EMULSIONS Concen- Shaking 30 min., Heating 125 F. Shake 10 min., Demulsifler tration, standing 30 min. 10 min. and set min. Set 2 hours p. p. m. set 10 min.

Oil 3.4 m Oil 3.1 cm 011 3.3 Pm Oil 2.9 cm. Polyvinyl methyl ether 300 Water 3.1 cm Water 3.4 cm Water 3.2 cm Water 3.6 cm. (water layer clear).

Table 4 DEMULSIFIOATION OF CRUDE OIL EMULSIONS This invention has been disclosed with respect to certain preferred embodiments. Various modifications and variations of these embodiments will become apparent to those skilled in the art, and it is to be understood that such modifications and variations are to be included within the spirit and purview of this application and the scope of the appended claims.

I claim:

1. A process for breaking water-in-oil type emulsions comprising subjecting such emulsions to the action of a polyvinyl lower alkyl ether having a K value of from about 10 to 200.

2. A process for breaking a water-in-oil type emulsion comprising subjecting such emulsion to the action of a polyvinyl alkyl ether having a K value of from about 10 to 200 selected from the group consisting of polyvinyl methyl ethers and polyvinyl ethyl ethers.

3. A process as defined in claim 2 wherein said polymeric alkyl ether is polyvinyl methyl ether.

4. A process as defined in claim 2 wherein said polymeric alkyl ether is polyvinyl ethyl ether.

5. A process as defined in claim 3 wherein said polyvinyl methyl ether has a K value of about 54.

6. A process as defined in claim 3 wherein said emulsion is a petroleum water-in-oil emulsion.

7. A process as defined in claim 6 wherein said emulsion is a crude oil emulsion.

8. A process as defined in claim 6 wherein said emulsion is a refinery type emulsion.

500 parts by weight per million parts by volume of said emulsion.

11. A process as defined in claim 4 wherein said emulsion is a crude oil emulsion.

12. A process as defined in claim 11 wherein said polyvinyl ethyl ether is employed in amounts of about 50 to parts by weight per million parts by volume of said emulsion.

13. A process as defined in claim 1 wherein the polyvinyl lower alkyl ether is employed in amounts of about 10 to about 500 parts by weight per million parts by volume of the said emulsions.

14. A process as defined in claim 1 wherein the polyvinyl lower alkyl ether is employed in amounts of about 15 to about 100 parts by Weight per million parts by volume of the said emulsions.

References Cited in the file of this patent UNITED STATES PATENTS 2,159,313 Blair et a1. May 23, 1939 2,521,950 Schildknecht Sept. 12, 1950 2,537,706 Rudofi Ian. 9, 1951 OTHER REFERENCES Whitby et al.: Synthetic Rubber, pub. 1954 by John Wiley and Sons of New York, pages 957 and 958. 

1. A PROCESS FOR BREAKING WATER-IN-OIL TYPE EMULSIONS COMPRISING SUBJECTING SUCH EMULSIONS TO THE ACTION OF A POLYVINYL LOWER ALKYL ETHER HAVING A K VALUE OF FROM ABOUT 10 TO
 200. 